Furnace construction



Feb. 18, 1930. R. D. FOLTZ FURNACE CONSTRUCTION Filed May 7, 1924 2 Sheets-Shee l Feb. 18, 1930. R. D. FOLTZ FURNACE CONSTRUCTION 2 Sheets-Sheet; 2

Filed May 7, 1924 Patented Feb. 18, 1930 UNITED STATES PATENT- OFFICE RAYMOND D. FOLTZ, OF EAST ORANGE, NEW JERSEY, A SSIGNOR TO M. H, DETRICK FURNACE CONSTRUCTION Application filed May 7, 1924. Serial No. 711,557.

This invention relates to the construction of furnaces designed to afford combustion chambers, heating chambers or the like, and adapted for employment in connection with steam boilers or other apparatus. The particular features of furnace construction with which the present invention is involved pertain to wall portions and the like designed to form parts of a heat confining or combustion chamher. In certain respects the subject-matter of the present invention constitutes an improvement upon various features of construction covered by my co-pending application Serial No. 684,698, filed January 7, 1924.

The general purpose of the present improvements resides in the provision of a flexible wall structure which may be constructed to extensive width and height without imposing undesirable weight upon its component refractories, which will permit repair or replacement of refractories in any limited portion of the structure without involving the demolition of adjacent parts, which will which will provide for the desired cooling of metallic portions of the structure, which will allow for the desired expansion and contraction of the refractory wall without opening leaks or imposing undesirable stresses upon the refractories, and which will provide for accurate control of air supply to various portions of the furnace chamber.

In the construction of certain furnaces, particularly some furnaces designed for the use of pulverized fuel, which is fed pneumatically and burned in suspension, it is desirable to employ combustion chambers of very con.- siderable height, among other reasons, for the purpose of affording the desired extent of circulation of the suspended fuel. In such high furnace walls constructed according customary manner, great Weight is lmposed on the refractories in the lower portions of the structure, which contributes to their disintegration. Moreover, because of their height, there is very considerable expansion and contraction vertically in the structure incident to the heating and cooling thereof. 50 For the control of combustion, it is sometimes desirable to admit combustion air at various points or levels within the furnace chamber, and to vary this air supply as different circumstances arise. In my co-pending application above referred to, I have illustrated and claimed a construction which contributes the desired flexibility to the wall structure, and relieves the refractories from excessive loading. In that application I have shown also a construction arranged to permit the admission of air into the combustion chamber. By the present invention I provide a further arrangement for the control of the air feeding and for the accommodation of vertical expansion and contraction in the structure, whereby both the refractories and the metallic supporting members are protected from injurious strains and against flame leakage.

Other and further objects of the invention will be pointed out hereinafter, indicated in the appended claims, or obvious to one skilled in the art upon an understanding of the preent disclosure. For the purpose of this application I have elected to show one certain form in which the invention may be embodied, but it is to be understood that the structure is susceptible of variation from that herein disclosed, Without departing from the invention which I claim.

In the drawings forming a part of this specification,

Fig. l is a detail in the nature of a part elevation of a portion of a furnace, showing parts of adjoined walls, one in elevation from the inside of the furnace chamber and the other in sectional elevation as along the line Fig. 2 is an enlarged detail of same;

Fig. 3 is an assembly view illustrating the arrangement of wall hangers and wall refractories, as seen from the outside, the frame structural members and sheathing wall portions being removed, and the assembly in part broken away;

Fig. 4 is a cross sectional detail taken substantially on line 4-4 of Fig. 1; and

Fig. 5 is a vertical sectional detail taken substantially on line 5-5 of Fig. 1.

The nature of the invention will best be a part of the understood by reference to the illustrative embodiments in detail. Let it be understood that in the construction shown in the drawings the reference characters 10 designate supporting members, shown in the form of co umns, which are afforded the necessary foundatio support at their lower ends. Such columns may be disposed in suitable arrangement about the area of the furnace chamber, as in accordance with assemblies illustrated and described in my co-pending application mentioned above. Upon these columns are carried transverse frame members 14, which may be madeof angle members, or be constituted of other structural shapes. These are arranged one above another in the plane of the structure, and extend generally in parallel relationship. They afford support for the wall hangers or brackets 16, which have tension arms 16 terminating in hooks 16 and the compression arms 16 terminating in feet 16. These hangers have also the tile retaining members 16 rising from the shelf portions 16' adjacent their lower ends. In the assembly, the hooks 16 are engaged over flanges of the supporting members 14 and the feet 16 abutted against the inner sides of such flanges on lower frame members. By this arrangement, each frame member cooperates with two rows of hangers, the compression arms of the upper row being interposed between the tension arms of those of the lower row. It will be observed that the tension and compression arms are formed with portions arranged in approximately horizontal disposal, and that upon these portions are provided the laterally extending flanges 16. Supported on the shelf portions 16 of each hanger, and engaged with the tile retaining portion 16, is a plurality of tiles 17. Except for the lowermost tile on each hanger, these are of such length that their inner ends align so as to form a substantially regular wall portion. The lowermost tile 17 on each hanger is shorter than the others, for the reason later explained. Generally, the tile 17 are of uniform width also, so that their lateral margins align to form straight joints with the tile on juxtaposed hangers. At intervals, however, narrower tile 17 may be inserted in order to afford the air ports (P). The frame members 14 also afi'ord support for brick 19 which are built up to form a sheathing wall, the areas about the hooks 16" being packed with asbestos 21, or other compressible insulating material. The tile supported on the hangers 16 co-operate to form the walls of the furnace chamber or combustion chamber. Preferably these tile are made of fire clay or suitable refractory material adapted to withstand the high temperatures. The brick 19 co-operate to form sheathing walls exterior of the refractory walls and spaced therefrom. These sheathing walls may be provided with an external covering of plate 20 which is secured to the frame members 14. At desired localities the sheathing wall may be apertured to afford damper openings which are controlled by adjustable dampers 23 which govern the admission of air into the space between the refractory wall and the sheathing wall.

The purpose of thus admitting air between said walls is for supplying combustion air to the interior of the furnace chamber and limiting the temperature of the wall refrac tories. The circulation of the air between the walls also is efiective to prevent overheating of the hangers and the frame members. Inasmuch as conditions of operation may vary, it is desirable to provide for distribution and control of the admitted air, and to render this possible the space between the furnace and sheathing walls is subdivided into compartments. This subdivision is made by courses of brick 25, which are supported on the flanges 16 of the wall hangers, and extend from the outer faces of the tile 17 to the inner faces of the brick 19. In this fashion, compartments of limited height, extending horizontally across the furnace wall, are provided, the inlet of air to the respective compartments being controlled independently, so that the admission of air through the ports (P) supplied by different compartments may-be independently varied.

Inasmuch as the respective tile are individually movable on the hangers to a limited extent, and each hanger with its supported series of tile is independently movable in the structure both upwardly and horizontally in the plane of the structure, it is obvious that the refractory wall will possess great flexibility, yet be retained securely in proper form. Although the refractory wall and its component sections have thus a certain mobility with respect to the sheathing wall, which is fixed, it is to be observed that, due to the fact that the partitions formed by the bricks 25 are carried on the hangers which carry the refractory wall and maintain the refractories in place, between the partitions and the inlet ports P is maintained to enable the desired control of air distribution to the various ports. In order to accommodate this flexibility in the structure, and protect the hangers rom injurious strains, and at the same time maintain the tightness of the wall, I have provided im roved construction at the junction of the wal portions carried on adjacent rows of hangers. It will be observed that the short tile 17 form a course which is short of the eneral inner wall surface formed by the ends of the tile 17. Also the length of the tile retaining members 16 is such as to leave a space between their upper ends and the shelf portions 16' of superjacent hangers suflicient to permit the detachment of tile from the retaining members 16 by upward movement, and

the proper relationship ber, such as three,

of the tile 17. The lengt l npompartments.

their withdrawal from the wall by horizontal movement inwardly. To fill this space I provide the la brick 40. These are of general L-shape, of approximately the same length as the tile 17, but preferably only a fraction of the width thereof, so that a certain num of the lap tile are required to fill the Width of the upright leg of the lap tile is such a to overlap the end of the short tile 17", while. its thickness is such as to fill the space between the short tile and the inner ends of the tile 17. The vertical dimensions of the tile 40, however, are not such as to fit closely between the courses of tile with which they are associated, but a substantial space is left which is closely packed with asbestos or other compressible refractory material 27 to form expansion joints. These expansion joints may be of such thickness as to give ample play to the hangers and the tile incident to thermal expansion, because-opening of the joint is prevented by the overlap of the tiles 40 and 17 By dividing the resting on the upstanding legs of the tile 40 and the other on the top of their rearwardly extending legs, as clearly shown in Fig. 2, the packing of the joint is rendered more secure, as the outer portion of the packing is protected by the upstanding legs from the direct heat and erosive effects of the furnace gases. The upstanding legs of the tile 40 extend across the inner margins of the shelves 16 ,-so that the latter are afforded complete protection from the hot furnace gases.

The general construction and various features thereof, herein disclosed but not claimed, are claimed in my copending application above identified.

What I claim is:

1. In furnace construction, the combina tion with supporting members, of wall brackets, refractories supported by the latter to form furnace wall portions, a sheathing wall spaced from the furnace wall to afford an air chamber, and members supported by the brackets subdividing said chamber into compartments.

2. In furnace construction, the combination with a sheathing, wall, of wall hangers, refractories supported by the latter to form a furnace wall spaced apart from the sheathing wall to afford an air chamber, and members supported by the hangers and subdividing the air chamber into compartments.

3. In furnace construction, in combination, a sheathing wall, refractories associated to form a furnace wall, wall hangers supporting said refractories apart from the sheathing wall to form an air chamber, air inlets to said chamber and partition members supported by the hangers dividing said chamber into compartments.

4. In furnace construct1on, 1n comb nation,

' a sheathing wall, wall hangers, refractories packing into two parts, onesupported by the latter apart from the sheathing wall to form a furnace wall spaced from the latter by an air chamber, and partition members subdividing the air chamber into compartments, said furnace wall being provided with ports affording communication between the furnace chamber and the several 5. In furnace construction, in combination, wall hangers, refractories supported thereon to form the wall of a furnace chamher, an external wall forming an air chamber outside the furnace wall, partition members associated with the hangers and subdividing the air chamber into compartments, the furnace Wall being provided with ports affording communication between the compartments and the furnace chamber, and means for controlling inlet of air to the compartments severally.

In furnace construction, in combination, wall hangers, refractories supported thereon in association to form a wall portion of the furnace chamber, an external Wall forming an air chamber outside the furnace Wall, said furnace wall being provided with ports at different elevations, partition members supported on adjacent hangers and subdividing the air chamber into compartments at different elevations, and means for controlling inlet of air to said compartments severally.

7. In furnace construction, wall hangers arranged in adjacent horizontal rows with portions of those in one row interposed between portions of those in another, refractories su ported on the hangers in association to orm the wall of a furnace chamber, an external wall enclosing the hangers to afford an air chamber externally of the furnace wall and partition members supported on adjacent hanger portions to subdivide said air chamber into compartments.

8. In furnace construction, in combination, supporting members, wall hangers having laterally extending arms engaging said supporting members, refractories supported on the hangers in association to form a furnace wall portion, a sheathing Wall associated with the furnace wall to form an air chamber, and partition members supported on the hanger arms to subdivide said air chamber 'into compartments.

9. In furnace wall construction, collater ally disposed hangers, parts thereon for supporting the furnace wall refractories, and parts on the hangers for supporting partition members externally of the furnace wall.

10. In furnace construction, a hanger comprising a portion for supporting a stack of wall refractories, and arms extending laterally therefrom whereby the hanger is mounted on a support, said arms including portions for supporting partition members collaterally of the wall refractories.

to form a furnace wall portion extending collaterally of the sheating wall and spaced therefrom to afford an intervening air chamber, and partition members supported on the brackets and subdividing the air chamber into compartments.

13. A furnace wall comprising upright wall sections, metallic shelf members supporting said sections independently one above another, and lap brick arranged at the top of a section and overlapping vertically a. portion of a superjacent section and its supporting shelf members, to afford an expansion joint.

14. A furnace wall comprising upright wall sections arranged in spaced relationship one above another, brackets supportin said wall sections independently, lap bricarranged at-the top of a section and overlapping vertical face section and its supporting brackets, and compressible refractory material disposed between the lap brick and the superjacent section.

'15. A furnace wall comprising refractories arranged to form upright wall sections disposed in spaced relationship one above another, brackets supporting the sections independently, tile-retaining members anchoring refractories in the sections against horizontal displacement from the wall, and lap brick arranged between sections and overlapping vertical face portions of the superjacent section, said lap brick being withdrawable horizontally from the wall.

16. A furnace wall comprising refractories arranged to form upright wall sections disposed one above another, intervening shelf members supporting the sections independently, said sections having lap brick disposed along a horizontal'margin thereof and formed to overlap vertical face portions of a proximate section and the intervening shelf members.

17. Furnace wall construction comprising frame members, tile supports thereon, refractories supported on said supports to form wall sections arranged one above another 2*: constitute the furnace chamber wall, a sheathing wall supported by the frame members in spaced collateral association with the furnace wall to afford an intervening air space, said air space being subdivided into portions of a super]acent separate air circulation lanes andithe tile supports having portions exposed to air circulation in $211 lanes, andrespective air lanes being provided with respective air inlets.

18'; structural element for furnace walls comprising a refractory tile having plane, parallel top and bottom faces and plane, parallel lateral sides and an anchorage slot extending through the'body of the tile between the lateral sides, and a-plurality of refractory lap brick adapted to rest in collateral relationship with their bottom faces on the upper face of the tile, said lap brick having parallel top and bottomfaces and parallel side faces and being L-shaped in side elevation with the leg of the L projecting opposite the bottom face. a V

19. Furnace wall construction'comprisin'g, in combination a supporting frame, a refractory :wall sections independently supported on the frame, a sheathing wall spaced from the refractory; wall to afford an intervening air space, and partition members supported with respective refractory wall sections and subdividing the airspace into separate air lanes.

20. In furnace construction, in combination, a wall supporting frame, hangers supportedon the frame collaterally thereof, refractories disposed between juxtaposed hangers and supported conjointly thereby, and

wall refractories arranged in wall sectionssupported by the hangers.

In testimony whereof I have hereunto subscribed my name.

RAYMDND D. FOLTZ. 

